Front Range Ozone Action Day Alert Until at least 4 p.m. 07/06/2021

The Colorado Department of Public Health and Environment and the Regional Air Quality Council have issued an OZONE ACTION DAY ALERT at 4 p.m. on Monday, July 5, 2021 for the Front Range Urban Corridor from Douglas County north to Larimer and Weld counties, including the Denver-Boulder area, Fort Collins and Greeley.

Although thunderstorms should keep ozone concentrations in the Good to Moderate range for most areas on Monday, ozone concentrations are expected to reach the Unhealthy for Sensitive Groups category on Tuesday for southern and western portions of the Denver metro area. This could impacts locations including Highlands Ranch and Golden for Tuesday afternoon and evening.

This Ozone Action Day Alert will remain in effect until at least 4 p.m. Tuesday, July 6, 2021.

For statewide conditions, forecasts and advisories, visit:
www.colorado.gov/airquality/colorado_summary.aspx

The highest Ozone related AQI at 3 o'clock PM Mountain Standard Time on July 5, 2021, is 84 which indicates Moderate ozone air quality. It was recorded by the NREL ambient ozone monitor. Unusually sensitive individuals may experience respiratory symptoms. Unusually sensitive people should consider reducing prolonged or heavy outdoor exertion.

The highest Particulate Matter (PM2.5) related AQI at 3 o'clock PM Mountain Standard Time on July 5, 2021, is 77 which indicates Moderate Particulate Matter (PM2.5) air quality. It was recorded by the I25DEN ambient monitor. Respiratory symptoms possible in unusually sensitive individuals, possible aggravation of heart or lung disease in people with cardiopulmonary disease and older adults. Unusually sensitive people should consider reducing prolonged or heavy exertion.

Front Range Air Quality Forecast & Colorado Smoke Outlook

FRONT RANGE AIR QUALITY FORECAST:
Monday, July 5, 2021, 2:00 PM MDT

Ozone concentrations are expected to be in the Good to Moderate range on Monday and the Good to Unhealthy for Sensitive Groups range on Tuesday.

-- On Monday, Unusually sensitive people should consider reducing prolonged or heavy exertion until 10pm throughout the Front Range region.

--On Tuesday, ozone concentrations in the Unhealthy for Sensitive Groups category will be confined to southern and western portions of the Denver metro area, including Highlands Ranch and Golden. In these areas, active children and adults, and people with lung disease, such as asthma, should reduce prolonged or heavy outdoor exertion from noon until 8pm on Tuesday. For everywhere else in the Front Range region, unusually sensitive people should consider reducing prolonged or heavy outdoor exertion from noon to 10pm on Tuesday.

Fine Particulate Matter concentrations are expected to be in the Good to Moderate range on Monday and the Good category on Tuesday. Moderate concentrations of fine particulates are due to the lingering health impacts associated with smoke from fireworks displays Sunday night and Monday morning. Unusually sensitive people should consider reducing prolonged or heavy exertion through midnight Monday night.

Carbon Monoxide concentrations are expected to be in the Good category on Monday and Tuesday.

Nitrogen Dioxide concentrations are expected to be in the Good category on Monday and Tuesday.

Visibility in Denver on Tuesday is expected to be Good to Moderate.

COLORADO SMOKE OUTLOOK:
Monday, July 5, 2021, 2:15 PM MDT

Relatively cool and moist weather has significantly decreased fire activity across the state. The larger wildfires in Colorado, including the Sylvan wildfire in southern Eagle County and the Muddy Slide wildfire in southern Routt County are expected to produce limited smoke on Monday and Tuesday. Any significant concentrations of smoke will be confined to locations in very close proximity to the wildfires during the overnight and early morning hours. No significant public health impacts are expected at this time. Drier weather during the middle and late part of the week could increase fire activity and smoke. Updates will be provided as the weather situation and wildfires evolve over the next few days.

What if there is a wildfire or smoke in your area?
The focus of the Colorado Smoke Outlook is on large fires (e.g., greater than 100 acres in size). Nevertheless, smoke from smaller fires, prescribed fires, and/or smoke from new fires not yet known to
CDPHE air quality meteorologists may cause locally heavy smoke. If there is smoke in your neighborhood, see the public health recommendations below.

Public health recommendations for areas affected by smoke:
If smoke is thick or becomes thick in your neighborhood you may want to remain indoors. This is especially true for those with heart disease, respiratory illnesses, the very young, and the elderly. Consider limiting outdoor activity when moderate to heavy smoke is present. Consider relocating temporarily if smoke is present indoors and is making you ill. IF VISIBILITY IS LESS THAN 5 MILES IN SMOKE IN YOUR NEIGHBORHOOD, SMOKE HAS REACHED LEVELS THAT ARE UNHEALTHY.

Summer Ozone Program
Ground-level ozone is an air pollution problem that impacts the health of all Coloradans. Exposure can cause acute respiratory problems and trigger asthma attacks. During Ozone Action Alerts, avoid rigorous outdoor activity during the heat of the day. Prolonged exposure can cause long-lasting damage to your lungs.

You CAN make a difference by doing your part to improve air quality along Denver's Front Range. Combining or skipping just two car trips a week has a positive impact on our air quality. Find other easy solutions that fit your lifestyle from Simple Steps. Better Air. ( www.SimpleStepsBetterAir.org ), a program of the Regional Air Quality Council.

WHAT IS AN ACTION DAY?: An Action Day for fine particulate matter, carbon monoxide, ozone or other pollutants indicates that either current air quality is unhealthy or conditions are expected to worsen later in the day or on the next day. Action Days for air pollutants generally indicate that air quality will be in either the Unhealthy or Unhealthy-for-Sensitive-Groups categories according to the Air Quality Index. Action Days always convey overarching public health recommendations, and, according to season, trigger a variety of mandatory and voluntary pollution prevention measures. For example, during the summer open burning is prohibited when an Action Day for ozone and/or fine particulates is in effect. During the winter, residential burning restrictions are in effect when an Action Day for Visibility is in effect.

For a detailed description of both the AIR QUALITY INDEX and the VISIBILITY STANDARD INDEX please visit www.colorado.gov/airquality/brochure.aspx

COLORADO OPEN BURN FORECAST: For those with permits for open burning, that is the burning of waste materials or vegetation outside, check the following webpage to find out if open burning is allowed today. Keep in mind that open burning is prohibited when an Action Day is in effect:
www.colorado.gov/airquality/burn_forecast.aspx

FOR CURRENT FRONT RANGE ACTION DAYS/ADVISORIES:
www.colorado.gov/airquality/advisory.aspx

FOR CURRENT AIR QUALITY CONDITIONS STATEWIDE:
www.colorado.gov/airquality/air_quality.aspx

SOCIAL MEDIA:
www.facebook.com/cdphe.apcd
twitter.com/cdpheapcd

AIR QUALITY NOTIFICATIONS:
www.colorado.gov/airquality/request_alerts.aspx (CDPHE automated e-mail alerts)
www.enviroflash.info/signup.cfm (CDPHE forecasts via automated e-mails from the EPA)